Posted: Jun 02, 2013 3:48 pm
laklak wrote:There is some statistical evidence that those with darker eye colors are more likely to suffer from SAD (seasonal affective disorder) than those with lighter eyes. Also, there is some evidence that the genes responsible for eye color are linked in some way to those controlling skin color, but the short answer is no one really knows, yet, what selection pressures were active.
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True, but it is not unreasonable to suppose that Africans have dark irises for the same reason that they have dark skin and dark hair - melanin absorbs UV more effectively when there is more of it, and more of it means dark brown.